Solid fire starting materials such as paper, twigs or sticks, pine cones or pinewood, and the like are customarily used as kindling to ignite other, longer-burning materials, principally wood, coal or charcoal briquettes. Such solid fire starting materials are generally safer than most liquid petroleum based fire starting materials, but are not without difficulties themselves, among which is a tendency to burn up before igniting the primary fuel.
Numerous attempts have been made to provide improved solid fire starting materials. For example, U.S. Pat. No. 4,272,252, issued June 9, 1981 to Altman, discloses a fire starting material comprising a rectangular block of porous cellulosic fiber board, such as cellulosic fiber insulating board, including such boards coated on one side with asphalt, made up of individual squares which can be broken off and soaked with mineral spirits (or "a combustible, volatile petroleum distillate"). The block is sealed within a burnable, multilayered envelope which is impervious to mineral spirit vapors, the envelope being made up of at least one cellophane layer to aid in the envelope's burning and at least one polyethylene layer to retard the envelope's burning. Similarly, U.S. Pat. No. 3,279,900, issued Oct. 18, 1966 to Naples, discloses a fire starting material for igniting charcoal comprising wood pulp, compressed wood fiber or felted fibrous pulp pressed into an approximately one half inch thick pad, containing cylindrical perforations or draft holes and impregnated with paraffin wax in an amount of about 10 to 20% of the total weight of the pad, while U.S. Pat. No. 3,395,003, issued July 30, 1968 to Alexander, also discloses a fire starting material made of a web, sheet or mat of wood pulp paper which is first dipped in hickory oil, then dried and treated in successive baths of citronella and paraffin oil. Such mats may be made up of repeated shapes supplied in a single structure so that portions of the structure may be broken away for use as kindling.
U.S. Pat. No. 3,726,652, issued Apr. 10, 1973 to Schick, discloses the use of a combustible solid fibrous material, such as Celotex fiber board, which has been impregnated with an oxidizing agent and a binder such as paraffin wax, as an ignition cap for a "primary combustible solid" such as petroleum coke.
Other prior art fire starting or kindling materials are disclosed in U.S. Pat. No. 3,351,444, issued Nov. 7, 1967 to Ryan et al, U.S. Pat. No. 2,854,321, issued Sept. 30, 1958 to Stanton, U.S. Pat. No.2,227,256, issued Dec. 31, 1940 to Haffner and U.S. Pat. No. 2,059,208, issued Nov. 3, 1936 to Chaney.
Another method used in the prior art to improve the ignition qualities of more difficultly ignitable fuels such as wood, coal and charcoal briquettes, particularly for cooking purposes, is to impregnate them with liquid flammable materials. If volatile materials are used as the impregnants, they tend to volatilize off while burning before igniting the primary fuel, and in any event introduce a serious safety hazard. Non-volatile impregnants--waxes or other paraffinic materials, for example--often do not provide enough heat by themselves, or ignite too slowly, to maintain combustion in the primary fuel. Disclosures relating to impregnating solid fuels with such materials can be found, for example, in U.S. Pat. No. 3,232,720, issued Feb. 1, 1966 to Kepple, U.S. Pat. No. 2,976,133, issued Mar. 21, 1961 to Stueler, and U.S. Pat. No. 2,107,054, issued July 24, 1935 to Haymond.